The popularity of skateboards has given rise to the desirability to mount a motor thereon whereby the skateboard becomes self-propelled. A conventional skateboard normally has pairs of front and rear wheels mounted thereunder for limited universal movement. Such mountings normally comprise a universal joint and an elastomeric bushing whereby both the front and rear wheels are adapted to pivot in an infinite number of planes. In addition to adversely affecting the drive characteristics transmitted to the driven rear wheel, the rear wheels tend to pivot in a horizontal plane which causes the rider's platform to wobble and become unstable and to also reduce needed traction of the rear wheels.
In addition, the motor mounted on the platform of a conventional skateboard normally drives one of the rear wheels by a single chain and a pair of sprockets to provide a relatively low drive ratio. Also, no centrifugal clutch or the like is employed in the drive train for a conventional motorized skateboard whereby throttle control must be regulated very carefully to prevent sudden accelerations or decelerations. Also, a kill-switch is normally not employed on the throttle control for a conventional motorized skateboard to stop the motor instantaneously should such become necessary.